Trays are used to transport a number of devices and materials in fabrication facilities. For example, trays are used to transport a deoxyribonucleic acid (DNA) sample, a semiconductor wafer die, a pharmaceutical drug, etc. The trays may be transported within a building or across buildings.
Sometimes the trays are placed in tray stack supports to protect the trays from falling during transportation. Multiple such tray stack supports are used to transport the trays. Also, the trays are transferred between tray stack supports. For example, a tray stack support may be designated to be sent to an entity A and another tray stack support may be designated to be sent to an entity B. A tray that includes wafer die having specifications provided by the entity A is to be transferred in the tray stack support from a tray stack support to the tray stack support designated to be sent to entity A. Similarly, a tray that includes wafer die for the entity B is to be transferred in the tray stack support designated for the entity B.
However, such transfer of trays between tray stacks to send the trays to tray stacks designated for particular entities may not be available.